Dietary Needs

  • Foods High in Magnesium

    The body only absorbs 20-50% of the magnesium you eat, so it is important to include high magnesium foods in your diet as much as possible.

    There is also some evidence that foods that are particularly high in calcium or phosphate can decrease magnesium absorption, so it may be best not to drink milk or cola type drinks with your meals as they are high in calcium and phosphate.

    The following foods are all high in magnesium:

    Vegetables
    Artichokes, red kidney beans, chick peas, spinach, mung beans, lentils, okra, baked beans, hummus, sweet potato, plantain, chard, kale, brussel sprouts

    Try adding beans and lentils to curries or stews. Try sweet potato mashed or baked instead of standard white potato.

    Nuts
    Peanuts, cashew nuts, hazelnuts, walnuts, pecans, brazil nuts, almonds, pine nuts
    Peanut butter, marzipan, chocolate nut spreads e.g. nutella

    You can choose salted nuts to increase your salt intake if you need to. If you are watching your weight, remember nuts are quite high calorie so keep your portion sizes small.

    Seeds
    Sesame seeds, pumpkin seeds, tahini

    Try sprinkling seeds over a salad or add to breakfast cereals. Can be toasted for a tasty snack as an alternative to nuts.

    Cereals
    Brown rice, wholemeal pasta, puffed wheat, Shredded Wheat, Bran Flakes, All Bran, Weetabix, Ready Brek, oatmeal, Shreddies, wholemeal and brown bread, oat cakes, wholemeal scones

    Protein foods
    Meat, fish, shellfish, oysters, Tofu, soya beans, nut roast, vegeburgers, Quorn

    Snacks
    Dark chocolate, tortilla chips, Twiglets, Bombay mix, Trail mix, popcorn, flapjacks

    Fruit
    Figs, dried apricots, dates

  • Foods High in Potassium

    Potassium is dissolvable in water, so try to avoid boiling high potassium foods to keep as much of the potassium as possible.

    The following foods are all high in potassium:

    Fruit
    Bananas, Grapes, Oranges, Strawberries, Mango, Rhubarb, Dried Fruit, Pineapple, Melon, Fresh Fruit Juices, Fresh Tomato Juice

    All fruits contain some potassium so try to eat a variety and aim for 5 portions of fruit/vegetables daily.

    Vegetables
    Mushrooms, spinach, broad beans, parsnips, tomato, beetroot, avocado,
    Baked beans, pulses e.g. lentils, kidney beans

    Consider steaming or microwaving vegetables rather than boiling, to minimise potassium losses during cooking

    Potatoes
    Jacket potatoes, roast potatoes, Chips, Potato waffles, instant potato products

    Potato that hasn’t been boiled will be higher in potassium.

    Savoury snacks
    Potato crisps and potato snacks, Nuts

    Chose salted varieties if you also need to increase your salt intake

    Biscuits & cakes
    All biscuits containing dried fruit, nuts or chocolate, Fruit cake, chocolate cake, any cake containing nuts

    Sweets/ chocolate
    Toffee, chocolate, fudge

    Drinks
    Instant/filter coffee, camp coffee, coffee essence, Cocoa, hot chocolate, malted milk drinks, Fruit juices, tomato juice, drinks containing a high proportion of fruit juice, Milk

    Miscellaneous
    Peanut butter, Bovril, Marmite, Evaporated and condensed milk, Tomato puree, tomato based sauces

  • Foods High in Salt

    Much of what you read about salt tells you that a high salt diet is bad for you. But for people with Gitelman and Bartter syndromes, this is not the case. They actually need a higher intake of salt to make up for the extra salt that their kidneys are getting rid of.

    It is possible to increase the salt in your diet without turning to highly processed, convenience type foods so you can still have a healthy diet, just one that is higher in salt.

    Here are some tips that may help:

    • Add salt to your food – it doesn’t matter if it is sea salt or table salt, it’s all still sodium chloride!
    • Smoked foods tend to be higher in salt e.g. smoked salmon, smoked haddock, kippers, smoked bacon.
    • Salted nuts, crisps or pretzels – nuts provided benefits including unsaturated fatty acids and antioxidants. Olives in brine are another higher salt snack. However, nuts and crisps are quite high calorie, so if you are watching your weight, keep portion sizes small.
    • Salted popcorn – this would be a good lower calorie alternative to nuts or crisps.
    • Ham, corned beef, sausages and other processed meats all have added salt.
    • Many cereals, breads and biscuits contribute a reasonable amount of salt to your diet.
    • Tinned foods e.g. soups, baked beans, fish in brine also contribute more salt to your diet.
    • Use sauces e.g. Worcestershire sauce, soy sauce, ketchup, brown sauce.
    • Marmite, Bovril or vegemite on toast or in sandwiches will add extra salt to your diet.
  • Foods Low in Salt

    A typical western diet contains much more salt (sodium chloride, table salt) than we need. The kidneys regulate the amount of salt in the body. Salt and water are handled together so if there is an excess of salt there is a proportionate excess of water. Salt in the diet also makes us thirsty so we take in more water to match our salty appetite. For healthy, physically active people, our high salt intake poses little risk. This is not so for people with certain kinds of kidney disease.

    If the kidneys can’t get rid of the extra salt and water they accumulate, it causes two problems. One is high blood pressure (hypertension). The other is swelling of the tissues where the extra fluid collects (oedema).  In extreme cases the excess fluid can accumulate in the lungs and cause serious breathing problems (pulmonary oedema).

    Patients on dialysis often retain too much salt. The water that goes with it causes them to gain weight between one dialysis treatment and the next.  Being told to cut down on how much water they should drink simply doesn’t work unless their salt intake is also reduced.

    Patients with other kidney disorders also risk gaining excess salt and water. This includes those with nephrotic syndrome and certain rare genetic conditions related to hypertension.  Diuretic medicines are often prescribed to make the kidneys release more salt and water into the urine.  If patients have a high salt intake this overcomes the benefit of the diuretic. Patients in these circumstances need to adopt a low salt diet.

    Everyday foods, especially processed foods such bread, butter, cooked meats, biscuits, sauces, soups and breakfast cereals all contain added salt. Prepared or take away meals are usually very high in salt. It is quite difficult to avoid excessive salt.  It helps if the patient or the family prepares food from raw ingredients and cooks for themselves. Specialist advice from a renal dietician is necessary. In time patients can learn how to enjoy nutritious food with taste and flavor but very little salt.

dietary needs version 1 updated June 2013
Written by Claire parslow, renal dietician, Cambridge university hospitals nhs trust and the Rarerenal.org operational management board